/Engine/Source/Runtime/GeometryCore/Public/MeshRegionBoundaryLoops.h
Find the edge loop border around a set of triangles of a Mesh. This is computed via local walk and so does not create any full-mesh data structures. However current implementation may not be efficient for large triangle sets. Algorithm terminates if a non-manifold boundary is detected, and returns false if some triangles are unused.
true if a single well-formed loop was found, false if non-manifold or failure case encountered
static bool GetTriangleSetBoundaryLoop ( const [FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) & Mesh, const [TArray](API\Runtime\Core\Containers\TArray)< int32 > & Tris, [FEdgeLoop](API\Runtime\GeometryCore\FEdgeLoop) & Loop )